-- Macaulay2 lists subsets in grevlex order
-- That is why we put the variables in the order shown below
S = QQ[x_12,x_13,x_23,x_14,x_24,x_34,x_15,x_25,x_35,x_45,x_16,x_26,x_36,x_46,x_56];
Gr26 = {x_12*x_34-x_13*x_24+x_14*x_23,
x_12*x_35-x_13*x_25+x_15*x_23,
x_12*x_36-x_13*x_26+x_16*x_23,
x_12*x_45-x_14*x_25+x_15*x_24,
x_12*x_46-x_14*x_26+x_16*x_24,
x_12*x_56-x_15*x_26+x_16*x_25,
x_13*x_45-x_14*x_35+x_15*x_34,
x_13*x_46-x_14*x_36+x_16*x_34,
x_13*x_56-x_15*x_36+x_16*x_35,
x_14*x_56-x_15*x_46+x_16*x_45,
x_23*x_45-x_24*x_35+x_25*x_34,
x_23*x_46-x_24*x_36+x_26*x_34,
x_23*x_56-x_25*x_36+x_26*x_35,
x_24*x_56-x_25*x_46+x_26*x_45,
x_34*x_56-x_35*x_46+x_36*x_45};